| 摘要: |
| [目的]了解黄土高原半湿润丘陵区不同森林类型林下植物群落的现状,为该区森林植被建设和管理提供科学依据.[方法]采用"标准地-样方"法,对黄土高原中部半湿润黄土丘陵区(延安)的林下植物群落进行调查,统计并计算林下植物群落的生活型谱、盖度、优势度及物种多样性.[结果](1)小叶杨、白桦、油松、油松+小叶杨、油松+白桦林地林下植物生活型谱均以高位芽植物种占绝对优势,白榆、刺槐、沙棘、茶条槭和侧柏林地则以非高位芽植物为主.(2)林下植物(灌木层-草本层)的总盖度大小顺序为小叶杨林、刺槐林(22.22%～22.65%)>油松+小叶杨林、白桦林、白榆林(9.78%～14.11%)>侧柏林、沙棘林、茶条槭林、油松 白桦林(3.72%～5.20%)>油松林(2.38%).(3)林下灌木层优势植物种类因地而异,并以苦糖果(Lonicera standishii)、牛奶子(Elaeagnus umbellate)、杠柳(Periploca sepium)和白刺花(Sophora davidii)最为常见;林下草本层优势植物种类以羊胡子草(Carex riges-cells)占绝对优势,其次有冰草(Agropyron cristatum)、胡枝子(Lespedeza yormosa)、野棉花(Urena lobata)和蒿类植物(Aremisia),(4)林下植物(灌木层-草本层)总的物种多样性指数和大小顺序为小叶杨林(7.29)>刺槐林、白桦林、油松林(6.03～6.61)>侧柏林、油松+小叶杨林(5.72～5.90)>茶条槭林、天然草地、油松+白桦林(4.44～4.85)>白榆林、沙棘林(3.49～3.50).[结论]该区林下植物群落盖度及其物种多样性普遍不高,多数阔叶乔木树种林下植物群落要比针叶树种和灌木林丰富,所以在针叶林中积极引进阔叶树种形成混交林,是增加林下植物盖度及其多样性,维持森林生态系统稳定性和可持续发展的有效途径. |
| 关键词: 黄土高原 半湿润丘陵区 林下植物群落 物种多样性 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金资助项目(30471376)；西北农林科技大学人才计划项目(2005) |
|
| Quantity characteristics of plants community under tree-layers of forests in semi-humid gullied rolling region of Loess Plateau |
|
|
| Abstract: |
| 【Objective】 The study on the quantities characteristics of plant community under tree-layer of forest can give scientific basis for the construction and management of forests.【Method】 Standard plot+Sample plot was taken to investigate the plants community under tree-layers of forests in semi-humid gullied rolling region of loess plateau (Yan’an).【Result】（1） Life form spectrum of plants under tree-layers in forests of Populus simonii,Betula platyphylla,Pinus tabulaeformis,Pinus tabulaeformis+Populus simonii,Pinus tabulaeformis+Betula platyphylla take phanerophytes as major type,while forests of Ulmus pumila,Robinia pseudoacia,Hippophae rhamnoides,Acer ginnala and Platycladus orientalis take therophtes instead.（2）The order of total plants coverage under tree-layers in forests is Populus simonii,Robinia pseudoacia（22.22%-22.65%）＞Pinus tabulaeformis+Populus simonii,Betula platyphylla,Ulmus pumila（9.78%-14.11%）＞Platycladus orientalis,Hippophae rhamnoides,Acer ginnala,Pinus tabulaeformis+ Betula platyphylla（3.72%-5.20%）＞Pinus tabulaeformis（2.38%）.（3）The dominant shrub species under tree-layers alter with forest types and popular with Lonicera standishii,Elaeagnus umbellate,Periploca sepium and Sophora davidii.Meanwhile,herb species under tree-layers dominate absolutely with Carex rigescens and companied with Agropyron cristatum,Lespedeza formosa,Urena lobata and Aremisia.（4）The order of indexes sum of plant diversity under tree-layers of forests is Populus simonii（7.29）＞Robinia pseudoacia,Betula platyphylla,Pinus tabulaeformis（6.03-6.61）＞Platycladus orientalis,Pinus tabulaeformis+Populus simonii（5.72-5.90）＞Acer ginnala,Pinus tabulaeformis+Betula platyphylla（4.44-4.85）＞Ulmus pumila,Hippophae rhamnoides（3.49-3.50）.【Conclusion】 Coverage and species diversities of plant communities under tree-layer of planted forests in this region are generally not high and they are relatively richer in most broad-leaved forests than those in needle-leaved forests and shrubs.So,introducing broad-leaved trees into needle-leaved forest and forming mixture is an effective way to increase plant diversity under tree-layer and maintain ecosystem stability and sustainable development of forest. |
| Key words: Loess Plateau semi-humid gullied rolling region plant community under tree-layer plant diversity |
